diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index 9b16480b374a..06d7f44643d6 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2542,11 +2542,10 @@ uart_configure_port(struct uart_driver *drv, struct uart_state *state,
 {
 	unsigned int flags;
 
-	/*
-	 * If there isn't a port here, don't do anything further.
-	 */
-	if (!port->iobase && !port->mapbase && !port->membase)
-		return;
+	/* If there isn't a port here, don't do anything further. */
+	if (uart_iotype_mmio(port->iotype) || uart_iotype_io(port->iotype))
+		if (!port->iobase && !port->mapbase && !port->membase)
+			return;
 
 	/*
 	 * Now do the auto configuration stuff.  Note that config_port
@@ -3249,6 +3248,8 @@ bool uart_match_port(const struct uart_port *port1,
 		return hub6_match_port(port1, port2);
 	else if (uart_iotype_mmio(port1->iotype))
 		return port1->mapbase == port2->mapbase;
+	else if (port1->iotype == UPIO_BUS)
+		return true;
 	else
 		return false;
 }
diff --git a/include/linux/serial_core.h b/include/linux/serial_core.h
index 66b1459d53fc..c4cc4f66af4b 100644
--- a/include/linux/serial_core.h
+++ b/include/linux/serial_core.h
@@ -437,6 +437,7 @@ enum uart_iotype {
 	UPIO_TSI	= SERIAL_IO_TSI,	/* Tsi108/109 type IO */
 	UPIO_MEM32BE	= SERIAL_IO_MEM32BE,	/* 32b big endian */
 	UPIO_MEM16	= SERIAL_IO_MEM16,	/* 16b little endian */
+	UPIO_BUS	= SERIAL_IO_BUS,	/* Serial bus I/O access (ex: SPI, I2C) */
 };
 
 struct uart_port {
diff --git a/include/uapi/linux/serial.h b/include/uapi/linux/serial.h
index de9b4733607e..e6f61538fc28 100644
--- a/include/uapi/linux/serial.h
+++ b/include/uapi/linux/serial.h
@@ -72,6 +72,7 @@ struct serial_struct {
 #define SERIAL_IO_TSI	  5
 #define SERIAL_IO_MEM32BE 6
 #define SERIAL_IO_MEM16	7
+#define SERIAL_IO_BUS	8
 
 #define UART_CLEAR_FIFO		0x01
 #define UART_USE_FIFO		0x02